BigCouch is a highly available, fault-tolerant, clustered, mostly api-compliant version of Apache CouchDB. While it appears to the end-user as one CouchDB instance, it is in fact one or more BigCouch nodes in an elastic cluster, acting in concert to store and retrieve documents, index and serve views, and serve CouchApps. BigCouch has been developed and is continually maintained by Cloudant.
Clusters behave according to concepts outlined in Amazon's Dynamo paper, namely that each BigCouch node can accept requests, data is placed on partitions based on a consistent hashing algorithm, and quorum protocols are used for read/write operations.
BigCouch is made available under an Apache 2.0 license. See the LICENSE file for details.
Please see http://bigcouch.cloudant.com/troubleshoot
Cloudant folks are usually hanging out in IRC. Freenode, channel #cloudant. There's also a Google Group.